Lighting Device For Alignment And Exposure Device Having The Same

Abstract

A ring shape lighting device, used for lighting the mark around the CCD camera, has a lighting device, a lighting brightness control device, a lighting height control device, a lighting color control device and a controller. The controller controls these devices and detects the marks using the CCD camera, by changing the lighting brightness at 1 percent step from 1 to 100 percent with different combinations of lighting height and lighting color. The device detects the mark contrasts using a contrast detection/determination device and detects the variance using a variance detection/determination device. The device then determines the best lighting condition based on the variance.

1 : A lighting device for alignment for lighting a board mark  61  provided on a printed circuit board  60  and a mask mark  51  provided on a mask  50  when aligning the printed circuit board  60  and the mask  50  based on the board mark  61  and the mask mark  51  by recognizing the board mark  61  and the mask mark  51  by an image recognition device, comprising:
 a lighting brightness control device for changing brightness of a lighting device, 
 a contrast detection device for detecting contrast between the board mark and the printed circuit board and contrast between the mask mark and the printed circuit board, 
 a variance detection device for detecting variance of positions of the board mark and the mask mark recognized plural times by the image recognition device, 
 a lighting condition decision device for determining appropriate lighting brightness as appropriate lighting condition among plurality of brightness changed by said lighting brightness control device based on contrast detected by said contrast detection device and variance detected by said variance detection device. 
 
     
     
         2 : An lighting device for alignment for lighting a board mark provided on a printed circuit board and a mask mark provided on a mask when aligning the printed circuit board and the mask based on the board mark and the mask mark by recognizing the board mark and the mask mark by an image recognition device, comprising:
 a lighting brightness control device for changing brightness of the lighting device,   a lighting height control device for changing lighting distance of the lighting device against said printed circuit board and said mask,   a contrast detection device for detecting contrast between the board mark and the printed circuit board and contrast between the mask mark and the printed circuit board,   a variance detection device for detecting variance of positions of the board mark and the mask mark recognized plural times by the image recognition device,   a lighting condition decision device for determining appropriate combination as appropriate lighting condition among plurality of combination of brightness changed by said lighting brightness control device and lighting distance changed by said lighting height control device based on contrast detected by said contrast detection device and variance detected by said variance detection device.   
     
     
         3 : An lighting device for alignment for lighting a board mark provided on a printed circuit board and a mask mark provided on a mask when aligning the printed circuit board and the mask based on the board mark and the mask mark by recognizing the board mark and the mask mark by an image recognition device, comprising:
 a lighting brightness control device for changing brightness of the lighting device,   a lighting height control device for changing lighting distance of the lighting device against said printed circuit board and said mask,   a lighting color control device for changing lighting color of the lighting device,   a contrast detection device for detecting contrast between the board mark and the printed circuit board and contrast between the mask mark and the printed circuit board,   a variance detection device for detecting variance of positions of the board mark and the mask mark recognized plural times by the image recognition device,   an lighting condition decision device for determining appropriate combination as appropriate lighting condition among plurality of combination of brightness changed by said lighting brightness control device, lighting distance changed by said lighting height control device and lighting color changed by said lighting color control device based on contrast detected by said contrast detection device and variance detected by said variance detection device.   
     
     
         4 : A lighting device for alignment as claimed in  claim 1 , wherein:
 Said lighting condition decision device at first determines candidates for appropriate lighting condition based on contrast detected by said contrast detection device and next determines said appropriate lighting condition among the candidates based on variance detected by said variance detection device.   
     
     
         5 : An exposure device having the lighting device for alignment as claimed in  claim 1 . 
     
     
         6 : A lighting device for alignment as claimed in  claim 2 , wherein:
 Said lighting condition decision device at first determines candidates for appropriate lighting condition based on contrast detected by said contrast detection device and next determines said appropriate lighting condition among the candidates based on variance detected by said variance detection device.   
     
     
         7 : An exposure device having the lighting device for alignment as claimed in  claim 2 . 
     
     
         8 : A lighting device for alignment as claimed in  claim 3 , wherein:
 Said lighting condition decision device at first determines candidates for appropriate lighting condition based on contrast detected by said contrast detection device and next determines said appropriate lighting condition among the candidates based on variance detected by said variance detection device.   
     
     
         9 : An exposure device having the lighting device for alignment as claimed in  claim 3 .